The effect of oxidation on the iodine values of phospholid in milk, butter and washed-cream serum

SummaryPhospholipid was isolated from milk, butter, and washed-cream serum by solvent extraction followed by simple counter-current distribution and thin-layer chromatography. Iodine values from fresh samples, determined by a micro-Wijs technique, ranged, for the cephalin fraction, from 70 to 86, for the lecithin fraction from 44 to 55, and for the sphingomyelin fraction from 36 to 44. In washed-cream serum, oxidation with copper and ascorbic acid led to reduction in extractable phosphorus, decreased chromatographic mobility of phospholipid and significant falls in the iodine values of the 3 phospholipid fractions. In milk, slight reductions in phospholipid iodine values were observed following copper-catalysed oxidation but they were not consistently significant. Iodine values of butter phospholipids remained unchanged even after gross oxidative quality deterioration.

Fate of tritium-labeled carnitine administered to dogs and rats

dl-Carnitine hydrochloride, tritiated nonspecifically, was purified and shown to have the same chemical and biological properties as the original compound (ß-hydroxy, γ-trimethylammonium butyrate). About one-third of administered material was excreted in urine during a 7-hr period following the intravenous injection of carnitine HCl (2 mg/kg) to dogs. Tritium not excreted appeared primarily in the trichloroacetic acid (TCA)-soluble fraction of various tissues, with approximately half that administered being found in skeletal muscle. The concentrations of tritium in TCA-soluble fractions of all organs examined except brain were 4–30 times higher than plasma concentrations. No evidence of carnitine degradation was found. The tritiated material in TCA-soluble extracts moved as single peaks in three different chromatographic systems, having the same RF values as those of known samples of carnitine. Tritium in chloroform-soluble fractions accounted for less than 1% of that administered. Of the organs examined, liver had the highest relative amount of incorporation of tritium into lipids, with all activity being found in unidentified phospholipids, chiefly in the lecithin fraction. The possible physiological significance of carnitine in muscle is briefly discussed.

THE INFLUENCE OF TETHELIN, AND OF OTHER ALCOHOL-SOLUBLE EXTRACTIVES FROM THE ANTERIOR LOBE OF THE PITUITARY BODY, UPON THE GROWTH OF CARCINOMATA IN RATS

1. The hypodermic administration of tethelin increases markedly the rate of growth of the primary tumor and the tendency to form metastases in rats inoculated with carcinoma, in this, as in other respects, reproducing the action of the whole anterior lobe of the pituitary body. 2. Other alcohol-soluble extractives of the anterior lobe of the pituitary body, with the exception of the lecithin fraction, exert no appreciable effect upon the growth of carcinomata in rats. 3. The lecithin fraction, as in previously reported experiments in which we employed lecithin obtained from eggs, causes evident retardation of the growth of carcinomata in rats.